What Causes Dementia? What Does Dementia Do to the Brain?
Dementia is a term that encompasses a group of progressive neurological disorders that affect memory, thinking, behaviour, and the ability to perform everyday tasks. As populations age globally, dementia is becoming one of the most pressing public health challenges, impacting not only those diagnosed but also their families and communities. Understanding what causes dementia and how it affects the brain is essential for early intervention, treatment, and care.
What Is Dementia?
Dementia is not a single disease but a broad term used to describe a range of symptoms associated with cognitive impairment. These symptoms interfere with daily life and social functioning. While memory loss is a hallmark sign, dementia also affects language, problem-solving, judgement, and mood.
Types of Dementia
There are several types of dementia, with varying causes and progression rates. The most common forms include:
- Alzheimer’s Disease: The most common form, accounting for 60–80% of dementia cases. Characterised by plaques and tangles in the brain.
- Vascular Dementia: Caused by reduced blood flow to the brain, often after a stroke or multiple mini-strokes.
- Lewy Body Dementia: Involves abnormal protein deposits called Lewy bodies that affect brain chemicals and function.
- Frontotemporal Dementia (FTD): Affects the frontal and temporal lobes, often causing changes in personality and behaviour.
- Mixed Dementia: A combination of two or more types, commonly Alzheimer’s and vascular dementia.
What Causes Dementia?
Dementia results from damage to brain cells that interferes with their ability to communicate with one another. The cause depends on the type of dementia:
1. Alzheimer’s Disease
Caused by the build-up of two abnormal proteins in the brain—beta-amyloid plaques and tau tangles—which disrupt communication between brain cells and lead to cell death.
2. Vascular Dementia
Triggered by reduced blood flow due to strokes, high blood pressure, or vascular damage. This deprives brain cells of oxygen and nutrients, leading to cognitive decline.
3. Lewy Body Dementia
Associated with clumps of alpha-synuclein protein in the brain, affecting memory, movement, and mood regulation.
4. Frontotemporal Dementia
Linked to abnormal protein accumulations that affect the brain’s frontal and temporal lobes. Genetics can also play a role.
Risk Factors for Dementia
While age is the strongest known risk factor, dementia is not a normal part of ageing. Other risk factors include:
- Family history and genetics
- Head injuries
- Cardiovascular disease
- High blood pressure and cholesterol
- Diabetes
- Smoking and alcohol abuse
- Obesity and poor diet
- Depression and isolation
How Does Dementia Affect the Brain?
Dementia progressively damages brain regions responsible for memory, reasoning, emotion, language, and motor skills. The effects differ based on the type:
- Hippocampus: Early damage here affects short-term memory (seen in Alzheimer’s).
- Frontal lobes: Impair judgement, reasoning, and personality (typical in FTD).
- Temporal lobes: Impact language and emotional processing.
- Parietal lobes: Affect spatial orientation and movement.
- Brain stem: Damage may cause changes in motor control, alertness, and sleep cycles (common in Lewy Body Dementia).
Common Symptoms of Dementia
Symptoms vary depending on the type and stage of dementia but may include:
- Memory loss that disrupts daily life
- Difficulty planning or solving problems
- Confusion about time or place
- Problems with language and communication
- Poor judgement and decision-making
- Changes in mood, personality, or behaviour
- Withdrawal from work or social activities
Diagnosis and Assessment
Early diagnosis is essential for managing dementia. Tests may include:
- Medical history review and physical exam
- Neurological exams to test reflexes and senses
- Cognitive tests (e.g., MMSE or MoCA)
- Brain imaging (MRI or CT scan)
- Blood tests to rule out other conditions
Can Dementia Be Treated or Prevented?
There is no cure for most forms of dementia, but treatment can help manage symptoms and slow progression.
Treatment Options:
- Medications: Cholinesterase inhibitors (donepezil, rivastigmine) and memantine can improve symptoms temporarily.
- Therapies: Cognitive stimulation, occupational therapy, and speech therapy help maintain function and independence.
- Lifestyle changes: Physical activity, mental engagement, and a balanced diet support brain health.
Preventive Measures for Brain Health
While not all dementia can be prevented, certain lifestyle changes may reduce risk:
- Exercise regularly
- Maintain a heart-healthy diet (e.g., Mediterranean diet)
- Stay socially active and mentally stimulated
- Control blood pressure, cholesterol, and blood sugar
- Avoid smoking and limit alcohol
- Manage stress and sleep health
Real-Life Example
Linda, a 68-year-old retired teacher, began experiencing memory lapses and difficulty finding words. After a comprehensive evaluation, she was diagnosed with early-stage Alzheimer’s disease. With medication, cognitive therapy, and support from her family, she continues to lead a fulfilling life, proving that early diagnosis and care make a difference.
Caring for Someone with Dementia
Caring for a loved one with dementia is emotionally and physically challenging. Support strategies include:
- Establishing a consistent routine
- Using memory aids and reminders
- Practising patience and empathy
- Creating a safe living environment
- Seeking support from local services and caregiver groups
Global Statistics
- Over 55 million people worldwide live with dementia (WHO, 2023)
- Nearly 10 million new cases are reported annually
- Women are more likely to be affected, partly due to longer life expectancy
Internal Resources for Further Reading
- 80.5% of People Have High Level of Depression
- What is a Mental Breakdown?
- Women’s Mental Health and Wellness
FAQs
Q: Is dementia the same as Alzheimer’s?A: No. Alzheimer’s is the most common type of dementia, but dementia refers to a broader set of symptoms and conditions.
Q: Can young people get dementia?A: Yes. Early-onset dementia can affect people under 65, though it is less common.
Q: Is memory loss always a sign of dementia?A: Not necessarily. Some memory issues may be due to stress, medication, or other conditions. A proper assessment is crucial.
Q: Can dementia be reversed?A: Most forms of dementia are irreversible, but early intervention can manage symptoms and improve quality of life.
Conclusion
Dementia is a complex condition that disrupts lives but understanding its causes and impact can help improve care, delay progression, and offer hope. Whether you're concerned for yourself or a loved one, recognising the signs and seeking help early can make a powerful difference. Through awareness, medical support, and community care, we can face dementia with strength and compassion.
